With the continuous improvement of examination means and methods, the diagnostic accuracy of tumors is gradually improved. However, there are a large proportion of tumors that do not have typical imaging features and thus are difficult to be diagnosed. Accurate diagnosis requires the combination of clinic, imaging and pathology. Among them, the pathological diagnosis is crucial for selecting a suitable treatment program. Needling biopsy (also known as puncture biopsy) is the main way to obtain the pathological diagnosis. Needling biopsy is a method for taking out and analyzing tumor cells from a subject. The advantage of this method is simple. In particular, it can be performed under local anesthesia in the outpatient department, and the success rate thereof can be greatly improved under the guidance of CT, MRI ultrasound and fluoroscopy. However, needling biopsy is performed by directly puncturing to the tumor site via the body's surface through a puncture needle which is hard and unbendable. When the tumor is situated in a deeper site or a position rich in blood vessels of the body, the puncture needle will easily cause damage or bleeding to normal tissues of the patient, while the patient is also suffering from pain and fear.
At present, Seldinger arterial intubation technique is very mature. Under the guidance of clinical imaging medicine (X-ray, CT, MR, B-us, etc.), a delicate instrument, such as a special catheter or guidewire is inserted into the lesion via percutaneous vascular route or an original channel in human body, so as to achieve a diagnostic imaging and treatment. This technique uses the metal guidewire via percutaneous vascular route to enter the blood vessel and reach the lesion. This method is simple in operation, slight in damage, and does not need to suture the blood vessels. Thus, it completely replaces previous methods which need to cut open the blood vessels surgically, and becomes a basic operation technique of modern interventional radiology. This method has achieved good effects in tumor thrombosis and drug perfusion, intra-arterial irradiation, prevention of radiation damage, chemotherapy, preoperative embolization of tumor blood vessels, vasoactive drugs and alcohol perfusion, etc.
The present disclosure uses a memory metal to constitute an intravascular puncture needle, and the puncture needle reaches the tumor site under the guidance of the interventional guidewire through the Seldinger intubation technique, and realizes the puncture of the tumor by deforming the memory metal into a needle shape, so as to draw out tumor cells through a guide tube in the puncture needle. Compared with the traditional puncture needle, the device of this disclosure has the following characteristics: small damage to the normal tissue of the patient, low bleeding probability, and basically no pain and so on.
The method of sampling by entering a tumor tissue via passing through blood vessels seems to be simple, but it is quite difficult actually. This is because the tumor is buried inside the body in a certain depth. If you want to reach the tumor by passing through the blood vessels, it needs to pass through blood vessels up to 1 to 2 m long. In addition, both the diameters and the wall thicknesses of the blood vessels are different, and the conditions inside the blood vessels are complicated. Therefore, there are strict requirements for the head portion and the body portion of the puncture system, so that a little carelessness could lead to the inability to pass through such long blood vessels or the inability to puncture the inner wall of the tumor blood vessel and enter the tumor.
Both during the passage through the blood vessel and during the biopsy sampling, the puncture system is an extremely critical. The difficulty of sampling through blood vessel is in that: the operator holds the extracorporeal end of the device, and the distance from the hand-held end and the puncture needle is 1 to 2 m. It is very difficult to accurately and conveniently operate the puncture needle to pass through the blood vessels, pierce the blood vessel walls, and enter the tumor tissue for sampling at far away from the needle, and thus requirements for various parts of the puncture system are extremely strict. Moreover, there are many contradictions between the passing through blood vessels and puncturing, for example, passing through blood vessels needs to avoid damage to the inner wall of blood vessels, while puncturing needs to be able to accurately pierce the tumor tissue; flexibility being required for passing through blood vessels, while rigidly being required for puncturing.
The puncture needle of this disclosure not only can pass through the blood vessels smoothly, but also can avoid the damage to blood vessels during passing through blood vessels, accurately puncture the tumor blood vessel walls and enter a tumor tissue for sampling.